1. Technical Field
The invention relates to a method of stimulating a drilled and cemented well for use in the production of hydrocarbons from a formation, when acid or an aggressive liquid is introduced through a perforated tubular for dissolving material.
2. Related Art
In related art, a cemented tubular, such as a casing or liner, may be perforated with an even density (number of perforations per unit length), and an improvement in stimulation fluid distribution may be attempted by changing the fluid characteristics, the injection rate or injection of dissolvable materials that temporarily seals off some of the perforations.
Pre-perforated liners may have an even distribution of perforations (number of perforations per unit length), but the use of such liners may suffer from the same disadvantages.
These methods for diverting stimulation fluids are normally not able to provide an even fluid distribution over longer intervals than about 250 meters.
EP 1 184 537 describes a method of stimulating a drilled well. The stimulation fluid is discharged into the annular space surrounding a well tubing through openings configured in the wall of the tubing in the longitudinal expanse of the tubing. The placement of the holes diverts the stimulation fluid along the entire length of the well tubing. The fluid influences the material on the surface of the wellbore.
The method described in EP 1 184 537 is not applicable to tubings or tubulars which are cemented into place. Furthermore, a provision for this method is the presence of a common and open annular volume between the tubular and the wellbore.